Polymerization of <i>p</i>‐cresyl glycidyl ether catalyzed by imidazoles I. The influence of the imidazole concentration, the reaction temperature, and the presence of isopropanol on the polymerization

Abstract

Abstract The polymerization of p ‐cresyl glycidyl ether catalyzed by imidazoles has been investigated as a model reaction for the polymerization of technical epoxy resins. The dependence of oligomer yield on time, temperature, and imidazole concentration, the distribution of the polymerization degrees, and the influence of isopropanol have been studied. The reaction rate and the average degree of polymerization are affected by the presence or absence of a secondary nitrogen on the imidazole, i.e., different results are obtained when 2‐ethyl, 4‐methyl imidazole (EMI) or 1‐methyl imidazole (1‐MIA) are used. 1‐MIA seems to be “precursor” of the catalyst rather than a catalyst by itself. The comparisons of CGE polymerizations catalyzed by 1‐MIA in the absence and presence of isopropanol show only quantitative differences: The polymerization in the presence of isopropanol is faster, and the average degree of polymerization is shifted to higher values. The activation energies of CGE polymerizations catalyzed by different imidazoles have been determined.